The present disclosure relates to tip dressing cutters for cutting distal ends of electrode tips for spot welding.
In general, a distal end of an electrode tip used for spot welding wears due to welding performed a predetermined number of times, or the condition of the distal end deteriorates due to an oxide film, etc. sticking onto the distal end. Therefore, the distal end has to be periodically cut by using a tip dresser.
Swarf which is produced at the time of cutting the distal end of the electrode tip by a cutting blade of the tip dresser may come into contact with the distal end of the electrode tip and scratch the distal end, or may twine around the tip dresser. Therefore, directly after a piece of swarf is produced by cutting the distal end by a component called a breaker, the piece of swarf is bent and curled (or fractured).
For example, International Patent Publication No. WO2013/061710 describes a tip dressing cutter including a holder which has a rotation axis extending in a vertical direction and has a substantially C shape when viewed in plan. The holder has a cutout recess formed therein. The cutout recess opens laterally outward and extends in the vertical direction to open both upward and downward. Part of the inner side surface of the cutout recess is formed as a mounting surface. The mounting surface extends along the longitudinal direction of the holder. The holder has a pair of curved surfaces as upper and lower surfaces. Each curved surface has a diameter gradually decreasing with decreasing distance to a center section of the holder. The shape of each curved surface corresponds to the shape of a distal end of an associated one of electrode tips when the center axes of the electrode tips coincide with the rotation axis of the holder. A cutting plate can be attached to the mounting surface. The cutting plate has a pair of cutting blades each corresponding to the shape of an associated one of the curved surfaces. The cutting plate and the breaker are fastened together to the mounting surface by a screw. The holder is turned with the distal ends of the electrode tips each being received by a corresponding one of the curved surfaces, thereby cutting the distal ends of the electrode tips by the cutting blades of the cutting plate, while pieces of swarf produced by cutting the distal ends by the cutting blades are bent by the breaker.